摘要： AIDS is said the biggest health challenge to both men and women in that area over the past few years. A.that it is B.to be C.that it has been D.to have been 答案 D 解析 句型sb. /sth. is said to+不定式.当不定式动作表示完成时.不定式需用完成形式.本题需用被动形式.因此选D项.

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